i fixed another hp70 tune at the track tonight
scat w 3500 convertor that had lost 1-2 shift
lemme know if you need help
Had delays due to fuel delivery issues. Dyno scheduled for next week. The compression is lower on this forced induction 6.4L (9.7:1) to run on 93 octane pump gas. Hoping for 550-650 (Dynojet dyno), or 450-550 (Mustang Dyno) as a baseline range with only 63lb injectors and 10psi boost.
Adding another 300Hp with bigger injectors and a smaller supercharger pulley may not be a good idea for the stock ZF 8HP70
OK. Thanks!
My first pre-dyno test was a 5.0 Mustang yesterday, on a second gear rolling start. Smoked it. I got a lot of WTFs and laughs. Since the new "stock" Mustang comes with anything from 315 to 480 HP, it probably was not the top performance stock version at 3,752 lbs. The fat 6,600 lbs. of Durango with 3 passengers in it without SRT or Hellcat badging was not supposed to do that
Last edited by Enthusiastic; 06-16-2023 at 04:31 AM.
it sounds crazy
spoolboy knows, he did not call me nutz
some of the switches got reversed somewhere during the latest revisions
thx hpt
DYNO RESULTS - 562WHP (SAME AS STOCK HELLCAT DURANGO):
Example Stock Hellcat Durango Specs and Dyno Reference Comparison:
Using an 8HP95 (900Nm) transmission, a "stock" 2021 SRT "Hellcat" 6.2L Durango produces 562WHP/531WT (according to Hennessey Performance) on 93 octane pump gas with stock tune, 9.5:1 compression ratio, 11.6 lbs. boost, and 57lb (600cc) injectors.
https://www.youtube.com/watch?v=n4WenoBjHjo
My Specs and Dyno Numbers:
Using an 8HP70 (700Nm) transmission, My 2017 Durango with forged 6.4L (392) produces 562.87WHP/524WT (Dynojet, yesterday) on 93 octane pump gas with a conservative tune, 9.7:1 compression ratio, 9.8lbs. boost, and 63 lb. (661cc) injectors. My 6.4L engine has 2 lbs. less boost than the reference 6.2L Hellcat motor and seems to have the same power but only RWD with the 8HP70.
Additional 6.4L Power Options:
If I reduce the supercharger pulley size by 1/4" from 3.75" to 3.5" using the same 63lb injectors, this should increase the boost to the same as the Hellcat and exceed stock Hellcat power by 50WHP for a total 612WHP. The 63lb injectors may be close to their limit and may require 80lb injectors. Also, this may be too much for the 8HP70 transmission.
A 1/2” pulley reduction to 3.25” would increase my boost to 13.8lbs. and increase the power to 662WHP or 100WHP over a stock hellcat Durango. [UPDATE 01-18-2024] Done. Boost is now over 13 PSI, estimated 680WHP
0-60:
The 6.4L Durango weighs at least 6,300 lbs. with larger engine, SRT aftermarket 9.5" wide rims, and 295/40ZR20 tires. Not sure what the 0-60 would be as I have to let off throttle before the 1>2 shift to avoid limp mode, then I can go WOT. The stock Hellcat Durango claims a 3.6 sec. 0-60 on a perfect run, if actually possible, without special tricks including no rear seats, cold day, special tune, launch mode etc. Regardless, off-the-line using the same tires with even HP, the AWD 8HP95 Hellcat will do better than the RWD 8HP70. I should be able to get under a 4.0 sec. 0-60 on the RWD Durango with the current configuration.
However, with more HP (smaller supercharger pulley) past the 0-60, I should be able to reel-in the stock Hellcat even with groceries .
Last edited by Enthusiastic; 01-18-2024 at 06:01 PM. Reason: added categories, clarification on 0-60
900 ft lb that means it comes with sipples billet drums
dont get burnt
dont pay 5 grand for a stock trans
on the phone i tried to suggest you learn how to set up scanner a lil better and log and find out if what you have is really shot before you swap it out
2019 challenger rt
k&N cold air intake
92mm hellcat throttlebody
ported 392 intake manifold
ported eagle heads
Cammotion custom 222/234 cam
stainless works long tube headers and catless mid pipes
3' catback with h-pipe & pypes violator mufflers
e-85 tuned
3.70 lsd
which version were you using when you wrote the last calibration?
Last edited by LilSick; 07-12-2023 at 07:17 PM.
I have a 2015 Ram cammed, procharged, and 3600 stall circle D. I am having this issue. How did you fix it?
In the past couple of months I have worked with a lot of RAM swaps (to ZF 8 speeds). It is quite a common issue.
The solution is a full transmission re-tune: Combination of torque converter, shift pressure, shift timing, shift RPM and line pressure.
Each case is unique (under my eyes). There is no "one size fits all", once every single engine and transmission are unique.
Thanks.
DodgeBoy.
YouTube: https://www.youtube.com/@dodgeboy2785
2019 challenger rt
k&N cold air intake
92mm hellcat throttlebody
ported 392 intake manifold
ported eagle heads
Cammotion custom 222/234 cam
stainless works long tube headers and catless mid pipes
3' catback with h-pipe & pypes violator mufflers
e-85 tuned
3.70 lsd
sure
email me the current tune and a good log
2019 challenger rt
k&N cold air intake
92mm hellcat throttlebody
ported 392 intake manifold
ported eagle heads
Cammotion custom 222/234 cam
stainless works long tube headers and catless mid pipes
3' catback with h-pipe & pypes violator mufflers
e-85 tuned
3.70 lsd